1. Field of the Invention
The invention relates to an image processing apparatus and method, and more particularly, it relates to an image processing apparatus and method capable of improving the color quality of an image signal regarding brightness, color temperature, and color deviation simultaneously.
2. Description of the Prior Art
Flat display panel (FDP) is going to be the main trend for display systems in the future, wherein the most noticeable FDP is liquid crystal display (LCD). Because LCD has advantages of thinness, light weight, low radiation, low power consumption, high resolution, high brightness, etc., it can be applied to a broad application range, such as personal computer, business billboard, home theater, etc. That is to say, LCD is the most comprehensive FDP.
When a conventional LCD displays a white image frame, the displayed color always tends to appear blue. In chromatology, the aforesaid phenomenon means that the color temperature on the LCD is relatively high. When the ratio of brightness intensity of three fundamental colors outputted by the LCD is different with the correct brightness intensity, the displayed color will be affected. At the same time, the user may see color deviation on the image frame. For example, blue sky may seem a little green, and white clouds may seem a little yellow. Therefore, there are some methods disclosed in prior arts, such as U.S. Pat. No. 6,911,785, for solving the aforesaid problems of color temperature and color deviation.
However, when color temperature and color deviation are adjusted based on gray levels, brightness relative to the gray levels will also deviate. In other words, although color temperature and color deviation may get better after being adjusted based on gray levels, brightness relative to the gray levels may get worse.
Therefore, the main scope of the invention is to provide an image processing apparatus and method capable of improving color quality of an image signal regarding brightness, color temperature, and color deviation simultaneously.